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How to decide values for simulated potential outcomes?

Hi all,

I am trying to learn how to use randomizr using the vignette.

In the section describing the need to simulate potential outcomes for a hypothetical experiment, I am unsure why values 2, -4, and -6 are used to simulate Y0? I am also unsure why values 6, 4, 2 are used for simulating Y1?

Also, it seems that both 4 and 6 have negative equivalents but 2 is both positive? Could someone please explain this to me? Apologies, but I am a little lost?

Good question! Those numbers are in there to illustrate how to build in treatment effect heterogeneity for a simulated experiment. here we’re letting the untreated potential outcomes be one function of hair, eye, and sex and we’re letting the treated potential outcomes be a different functino of those same variables.

These are not “correct” values, they are arbitrary values used to illustrate how one might create potential outcomes that vary with subject characteristics. Does that help?

Thanks very much for the reply! I am still a little lost to be honest? Even if they are arbitrary values, how do you decide what these arbitrary values should be in order to create a meaningful simulation?

Also, why did the assignment of 2 remain positive for both Y1 and Y0 outcomes?